TBN and Performance Booster

ABSTRACT

A lubricating oil composition including greater than 50% by weight of a base oil, based on the total weight of the lubricating oil composition and an additive for boosting the TBN of the lubricating oil without increasing the sulphated ash content. Also disclosed is a method for boosting the TBN of the lubricating oil composition as measured by both ASTM D-2896 and ASTM D-4739 without increasing the sulphated ash content by adding a TBN booster. The TBN booster can also be employed to improve results for the lubricating oil composition in a ball rust test and certain of the TBN boosters exhibit outstanding seal compatibility.

TECHNICAL FIELD OF THE INVENTION

The present disclosure relates to additives for lubricating oil compositions including nitrogen-containing compounds, lubricating oils containing the additives, and methods for lubricating an engine. The nitrogen-containing compounds used in the lubricating oils of the disclosure act as ashless TBN boosters and the additized lubricating oils are able to meet or exceed engine fluid specifications for different makes of vehicles.

BACKGROUND OF THE INVENTION

Environmental concerns have called for increased restrictions on emission standards for internal combustion engines. Current emission standards require that heavy duty diesel lubricants have maximum sulfated ash, phosphorus and sulfur contents, also known as “SAPS” for Sulfated Ash, Phosphorus, and Sulfur. In order to meet these standards, the treat rates of some additives that contain phosphorus, sulfur and ash-containing lubricant additives are being reduced to meet the SAPS standards. In addition to meeting SAPS standards, next generation oils will need lower calcium contents to prevent low speed pre-ignition.

These engines produce acidic byproducts of combustion that induce corrosion and decrease the lifetime of the engine. To counteract these problems, overbased calcium sulfonate detergents have been used to increase the total base number (TBN) of the lubricating composition. However, overbased calcium sulfonate contributes to the calcium and ash content. Simply reducing the amount of overbased calcium detergent will not mitigate the situation, since causes a corresponding reduction of the TBN value, as measured by ASTM D-2896 and ASTM D-4739, and causes a performance reduction in the Ball Rust Test. Therefore, an alternative option for increasing TBN and improving the performance in the Ball Rust Test that does not also significantly increase the calcium content of the lubricating oil is sought.

U.S. Pat. Nos. 5,525,247, 5,672,570, and 6,569,818 are directed to “low ash lubricating oil compositions that replace overbased detergents with one or more neutral detergents.

Several disclosures relate to nitrogen-containing compounds that may be used to replace calcium sulfonate detergents in order to overcome lower basicity as measured by ASTM D-2896. For example, US 2007/0203031 suggests use of high TBN nitrogen-containing dispersants as ashless TBN sources. U.S. Pat. No. 5,232,614 suggests use of para-phenylenediamines as antioxidants for lubricating oil compositions.

US 2011/0105374 A1 is directed to monoaryltrialkyl phenylenediamine compounds that are used as ashless TBN sources and are said to be compatible with fluoroelastomeric engine seal materials and to meet copper corrosion requirements.

An object of the present disclosure is to overcome low basicity as measured by ASTM D-2896-15 and ASTM D-4739-11 and provide improved Ball Rust Test results to meet emission standards and increase the lifetime of engines.

SUMMARY OF THE INVENTION

In a first aspect, the disclosure relates to a lubricating oil composition including greater than 50% by weight of a base oil, based on the total weight of the lubricating oil composition and an additive composition comprising one of:

(i) a reaction product of a dicyclohexyl carbodiimide with a primary or a secondary amine, and

(ii) at least one compound of the Formula (I):

wherein R′, R″, and R′″ are independently selected from the group consisting of a hydrogen, or a hydrocarbyl groups of about 1 to about 50 carbon atoms.

In certain embodiments, the lubricating oil composition includes a reaction product of a dicyclohexyl carbodiimide with a primary or secondary amine.

In certain embodiments, the lubricating oil composition comprises at least one compound of the Formula (I). In some embodiments, R′ is hydrocarbyl group having from about 4 to about 15 carbon atoms, or from about 6 to about 12 carbon atoms, and R″ and R′″ are hydrocarbyl groups having from about 4 to about 15 carbon atoms, or about 6 to about 12 carbon atoms.

In certain embodiments, the lubricating oil composition comprises a reaction product of dicyclohexyl carbodiimide with a primary amine.

In certain embodiments, the lubricating oil composition comprises a reaction product of dicyclohexyl carbodiimide with a secondary amine.

In certain embodiments, the additive composition comprises a compound of the Formula (I) selected from the group consisting of N-dodecyl-N′N″-dicyclohexylguanidine, N-2-ethylhexyl-N′,N″-dicyclohexylguanidine, N-benzyl-N′,N″-dicyclohexylguanidine, N-cyclohexyl-N′-dicyclohexyl-N″-cyclohexylguanidine, N-oleyl-N′,N″-dicyclohexylguanidin and N,N-dihexyl-N′,N″-dicyclohexylguanidine.

In another aspect, the disclosure relates to a lubricating oil composition including greater than 50% by weight of a base oil, based on the total weight of the lubricating oil composition and an additive composition comprising one of:

-   -   (i) a reaction product of a polyamine containing at least one         primary amino group and at least one compound of the following         Formulas (II)-(III):

wherein R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms and R₂ is selected from hydrogen, or a hydrocarbyl group of 1 to 50 carbon atoms; and in the compounds of the Formula (III) n is selected such that the compounds have a total number average molecular weight (Mn) of 10,000 to 70,000; and

-   -   (ii) a compound of one of the following Formulas (IV) to (V):

wherein R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms, R₂ is selected from hydrogen, or a hydrocarbyl group of 1-50 carbon atoms, R₇ is an amino group and in the compounds of the Formula (IV) n is selected such that the compounds have a total number average molecular weight Mn of 10,000 to 70,000.

In another aspect, the disclosure relates to a lubricating oil composition including greater than 50% by weight of a base oil, based on the total weight of the lubricating oil composition and an additive composition comprising a compound of the Formula (VI):

wherein R₆ is a hydrocarbyl group having 1-20 carbon atoms, more preferably, 2-18 carbon atoms and most preferably 4 to 12 carbon atoms.

In all of the foregoing embodiments, the additive composition may further comprise a detergent. In all of the foregoing embodiments, the detergent may be an overbased calcium sulfonate detergent.

In all the foregoing embodiments, the total overbased calcium detergent content delivered to the lubricating oil composition may be no more than 3 wt. %, more preferably no more than 2 wt. %, and even more preferably no more than 1.1 wt. % based on the total weight of the lubricating oil composition.

In all the foregoing embodiments, the total sulfated ash content may be about 2 wt. % or less, or about 1.5 wt. % or less, or about 1 wt. % or less.

In all the foregoing embodiments, the lubricating oil composition may be an engine oil.

In all the foregoing embodiments, the lubricating oil may exhibit an increase in TBN of from about 0.2 to about 2, more preferably, from about 0.4 to about 1.5, or, even more preferably, from about 0.5 to about 1.2, wherein the TBN is measured by ASTM D-4739 and the increase in the TBN is determined relative to a same composition in the absence of component (i) or (ii).

In another embodiment, the disclosure relates to a method of boosting TBN as measured by ASTM D-4739. The method includes the step of adding to a lubricating oil any of the foregoing reaction products or the compounds of the formulae (I) and (IV)-(VI). In certain embodiments, the boosted TBN is determined relative to a same composition in the absence of the reaction product(s) or the compound(s) of the Formulae (I) and (IV)-(VI).

In all the foregoing embodiments, the lubricating oil may exhibit an increase in TBN of about 0.2 to about 2, more preferably, from about 0.4 to about 1.5, or, even more preferably, from about 0.5 to about 1.2, wherein TBN as measured by ASTM D-4739 is determined relative to a same composition in the absence of anyone of the Formulae (I) and (IV)-(VI).

In another embodiment, the disclosure relates to a method of boosting performance in a Ball Rust Test, comprising the step of adding to a lubricating oil composition any of the foregoing reaction products or the compounds of the formulae (I) and (IV)-VI). The performance of the Ball Rust Test is determined relative to a same composition in the absence of the reaction product(s) or the compound(s) of the formulae (I) and (IV)-VI).

In certain embodiments, the present invention may also provide lubricating oil compositions that reduce or minimize deleterious effects on seals.

Additional features and advantages of the disclosure may be set forth in part in the description which follows, and/or may be learned by practice of the disclosure. The features and advantages of the disclosure may be further realized and attained by means of the elements and combinations particularly pointed out in the appended claims.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure, as claimed.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “hydrocarbyl” is used in its ordinary sense, which is well-known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character. Examples of hydrocarbyl groups include:

-   -   (a) hydrocarbon substituents, that is, aliphatic (e.g., alkyl or         alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl)         substituents, and aromatic-, aliphatic-, and         alicyclic-substituted aromatic substituents, as well as cyclic         substituents wherein the ring is completed through another         portion of the molecule (e.g., two substituents together form an         alicyclic moiety);     -   (b) substituted hydrocarbon substituents, that is, substituents         containing non-hydrocarbon groups which, in the context of this         disclosure, do not alter the predominantly hydrocarbon         substituent (e.g., halo (especially chloro and fluoro), hydroxy,         alkoxy, mercapto, alkylmercapto, nitro, nitroso, amino,         alkylamino, and sulfoxy); and     -   (c) hetero substituents, that is, substituents which, while         having a predominantly hydrocarbon character, in the context of         this disclosure, contain other than carbon in a ring or chain         otherwise composed of carbon atoms. Heteroatoms may include         sulfur, oxygen, and nitrogen, and encompass substituents such as         pyridyl, furyl, thienyl, and imidazolyl. In general, no more         than two, for example, no more than one, non-hydrocarbon         substituent will be present for every ten carbon atoms in the         hydrocarbyl group; typically, there will be no non-hydrocarbon         substituents in the hydrocarbyl group.

“Alkyl” refers to and includes saturated linear, branched, or cyclic hydrocarbon structures and combinations thereof. Particular alkyl groups are those having 1 to 100 carbon atoms. More particular alkyl groups are those having 1 to 20 carbon atoms, and even more particularly 1-18 carbon atoms. When an alkyl residue having a specific number of carbons is named, all geometric isomers having that number of carbons are intended to be encompassed and described; thus, for example, “butyl” is meant to include n-butyl, sec-butyl, iso-butyl, tert-butyl and cyclobutyl; “propyl” includes n-propyl, iso-propyl and cyclopropyl. This term is exemplified by groups such as methyl, t-butyl, n-heptyl, octyl, nonyl, dodecyl, cyclohexylmethyl, cyclopropyl and the like. Cycloalkyl is a subset of alkyl and can consist of one ring, such as cyclohexyl, or multiple rings, such as adamantyl. A cycloalkyl comprising more than one ring may be fused, spiro or bridged, or combinations thereof. In fused ring systems, one or more of the rings can be aryl or heteroaryl. A cycloalkyl having more than one ring where at least one ring is aromatic may be connected to the parent structure at either a non-aromatic ring position or at an aromatic ring position. In one variation, a cycloalkyl having more than one ring where at least one ring is aromatic is connected to the parent structure at a non-aromatic ring position. A preferred cycloalkyl is a saturated cyclic hydrocarbon having from 3 to 13 annular carbon atoms. A more preferred cycloalkyl is a saturated cyclic hydrocarbon having from 3 to 7 annular carbon atoms. Examples of cycloalkyl groups include adamantyl, decahydronaphthalenyl, cyclopropyl, cyclobutyl, cyclopentyl and the like.

“Alkenyl” refers to an unsaturated hydrocarbon group having at least one site of olefinic unsaturation (i.e., having at least one moiety of the formula C═C) and preferably having 2 to 100 carbon atoms. More particular alkenyl groups are those having 2 to 20 carbon atoms, and even more particularly 2-18 carbon atoms and even more particularly 3 to 10 carbon atoms. Examples of alkenyl include but are not limited to propenyl, octenyl, nonenyl, and oleoyl.

“Alkynyl” refers to an unsaturated hydrocarbon group having at least one site of acetylinic unsaturation (i.e., having at least one moiety of the formula C≡C) and preferably having 2 to 100 carbon atoms. More particular alkenyl groups are those having 2 to 20 carbon atoms, and even more particularly 2-18 carbon atoms.

“Acyl” refers to substituted or unsubstituted groups selected from H—C(O)—, alkyl-C(O)—, alkenyl-C(O)—, alkynyl-C(O)—, aryl-C(O)—, heteroaryl-C(O)—, and heterocyclic-C(O)—.

“Acyloxy” refers to substituted or unsubstituted groups selected from H—C(O)O—, alkyl-C(O)O—, alkenyl-C(O)O—, alkynyl-C(O)O—, aryl-C(O)O—, heteroaryl-C(O)O—, and heterocyclic-C(O)O—.

“Aryl” refers to an unsaturated aromatic carbocyclic group having a single ring (e.g., phenyl) or multiple condensed rings (e.g., naphthyl or anthryl) which condensed rings may or may not be aromatic. In one variation, the aryl group contains from 6 to 14 annular carbon atoms. An aryl group having more than one ring where at least one ring is non-aromatic may be connected to the parent structure at either an aromatic ring position or at a non-aromatic ring position. In one variation, an aryl group having more than one ring where at least one ring is non-aromatic is connected to the parent structure at an aromatic ring position. The term “aryl” also includes aromatic compounds that include alkyl, alkenyl, alkylaryl, amino, hydroxyl, alkoxy, halo substituents, and/or heteroatoms including, but not limited to, nitrogen, oxygen, and sulfur.

“Heteroaryl” refers to an unsaturated aromatic carbocyclic group having from 2 to 10 annular carbon atoms and at least one annular heteroatom, including but not limited to heteroatoms such as nitrogen, oxygen and sulfur. A heteroaryl group may have a single ring (e.g., pyridyl, furyl) or multiple condensed rings (e.g., indolizinyl, benzothienyl) which condensed rings may or may not be aromatic. A heteroaryl group having more than one ring where at least one ring is non-aromatic may be connected to the parent structure at either an aromatic ring position or at a non-aromatic ring position. In one variation, a heteroaryl group having more than one ring where at least one ring is non-aromatic is connected to the parent structure at an aromatic ring position.

“Aralkyl” refers to a residue in which an aryl moiety is attached to an alkyl residue and wherein the aralkyl group may be attached to the parent structure at either the aryl or the alkyl residue. Preferably, an aralkyl is connected to the parent structure via the alkyl moiety. A “substituted aralkyl” refers to a residue in which an aryl moiety is attached to a substituted alkyl residue and wherein the aralkyl group may be attached to the parent structure at either the aryl or the alkyl residue.

“Alkoxy” refers to the group alkyl-O—, which includes, by way of example, methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, tert-butoxy, sec-butoxy, n-pentoxy, n-hexoxy, 1,2-dimethylbutoxy, and the like. Similarly, alkenyloxy refers to the group “alkenyl-O—” and alkynyloxy refers to the group “alkynyl-O—”. “Substituted alkoxy” refers to the group substituted alkyl-O.

As used herein, the term “percent by weight”, unless expressly stated otherwise, means the percentage the recited component represents to the weight of the entire composition.

The terms “soluble,” “oil-soluble,” or “dispersible” used herein may, but does not necessarily, indicate that the compounds or additives are soluble, dissolvable, miscible, or capable of being suspended in the oil in all proportions. The foregoing terms do mean, however, that they are, for instance, soluble, suspendable, dissolvable, or stably dispersible in oil to an extent sufficient to exert their intended effect in the environment in which the oil is employed. Moreover, the additional incorporation of other additives may also permit incorporation of higher levels of a particular additive, if desired.

The term “TBN” as employed herein is used to denote the Total Base Number in mg KOH/gram of sample, as measured by one or more of the methods of ASTM D-2896 or ASTM D-4739 or DIN 51639-1.

Lubricants, combinations of components, or individual components of the present description may be suitable for use in various types of internal combustion engines. Suitable engine types may include, but are not limited to heavy duty diesel, passenger car, light duty diesel, medium speed diesel, motorcycle and marine engines. An internal combustion engine may be a diesel fueled engine, a gasoline fueled engine, a natural gas fueled engine, a bio-fueled engine, a mixed diesel/biofuel fueled engine, a mixed gasoline/biofuel fueled engine, an alcohol fueled engine, a mixed gasoline/alcohol fueled engine, a compressed natural gas (CNG) fueled engine, or mixtures thereof. A diesel engine may be a compression ignited engine. A gasoline engine may be a spark-ignited engine. An internal combustion engine may also be used in combination with an electrical or battery source of power. An engine so configured is commonly known as a hybrid engine. The internal combustion engine may be a 2-stroke, 4-stroke, or rotary engine. Suitable internal combustion engines include marine diesel engines (such as inland marine), aviation piston engines, low-load diesel engines, and motorcycle, automobile, locomotive, and truck engines.

The internal combustion engine may contain components of one or more of an aluminum-alloy, lead, tin, copper, cast iron, magnesium, ceramics, stainless steel, composites, and/or mixtures thereof. The components may be coated, for example, with a diamond-like carbon coating, a lubricated coating, a phosphorus-containing coating, molybdenum-containing coating, a graphite coating, a nano-particle-containing coating, and/or mixtures thereof. The aluminum-alloy may include aluminum silicates, aluminum oxides, or other ceramic materials. In one embodiment the aluminum-alloy is an aluminum-silicate surface. As used herein, the term “aluminum alloy” is intended to be synonymous with “aluminum composite” and to describe a component or surface comprising aluminum and another component intermixed or reacted on a microscopic or nearly microscopic level, regardless of the detailed structure thereof. This would include any conventional alloys with metals other than aluminum as well as composite or alloy-like structures with non-metallic elements or compounds such with ceramic-like materials.

The lubricating oil composition for an internal combustion engine may be suitable for any engine lubricant irrespective of the sulfur, phosphorus, or sulfated ash (ASTM D-874) content. The sulfur content of the engine oil lubricant may be about 1 wt % or less, or about 0.8 wt % or less, or about 0.5 wt % or less, or about 0.3 wt % or less, or about 0.2 wt % or less. In one embodiment the sulfur content may be in the range of about 0.001 wt % to about 0.5 wt %, or about 0.01 wt % to about 0.3 wt %.

The phosphorus content may be about 0.2 wt % or less, or about 0.1 wt % or less, or about 0.085 wt % or less, or about 0.08 wt % or less, or even about 0.06 wt % or less, about 0.055 wt % or less, or about 0.05 wt % or less. In one embodiment the phosphorus content may be about 50 ppm to about 1000 ppm, or about 325 ppm to about 850 ppm.

The total sulfated ash content may be about 2 wt % or less, or about 1.5 wt % or less, or about 1.1 wt % or less, or about 1 wt % or less, or about 0.8 wt % or less, or about 0.5 wt % or less. In one embodiment the sulfated ash content may be about 0.05 wt % to about 0.9 wt %, or about 0.1 wt % or about 0.2 wt % to about 0.45 wt %. In another embodiment, the sulfur content may be about 0.4 wt % or less, the phosphorus content may be about 0.08 wt % or less, and the sulfated ash is about 1 wt % or less. In yet another embodiment the sulfur content may be about 0.3 wt % or less, the phosphorus content is about 0.05 wt % or less, and the sulfated ash may be about 0.8 wt % or less.

In one embodiment the lubricating oil composition is an engine oil, wherein the lubricating oil composition may have (i) a sulfur content of about 0.5 wt. % or less, and/or (ii) a phosphorus content of about 0.1 wt. % or less.

In one embodiment the lubricating oil composition is suitable for a 2-stroke or a 4-stroke marine diesel internal combustion engine. In one embodiment the marine diesel combustion engine is a 2-stroke engine. In some embodiments, the lubricating oil composition is not suitable for a 2-stroke or a 4-stroke marine diesel internal combustion engine for one or more reasons, including but not limited to, the high sulfur content of fuel used in powering a marine engine and the high TBN required for a marine-suitable engine oil (e.g., above about 40 TBN in a marine-suitable engine oil).

In some embodiments, the lubricating oil composition is suitable for use with engines powered by low sulfur fuels, such as fuels containing about 1 to about 5% sulfur. Highway vehicle fuels contain about 15 ppm sulfur (or about 0.0015% sulfur).

Low speed diesel typically refers to marine engines, medium speed diesel typically refers to locomotives, and high speed diesel typically refers to highway vehicles. The lubricating oil composition may be suitable for only one of these types or all.

Further, lubricants of the present description may be suitable to meet one or more industry specification requirements such as ILSAC GF-3, GF-4, GF-5, GF-6, PC-11, CI-4, CJ-4, ACEA A1/B1, A2/B2, A3/B3, A3/B4, A5/B5, C1, C2, C3, C4, C5, E4/E6/E7/E9, Euro 5/6, Jaso DL-1, Low SAPS, Mid SAPS, or original equipment manufacturer specifications such as Dexos™ 1, Dexos™ 2, MB-Approval 229.51/229.31, VW 502.00, 503.00/503.01, 504.00, 505.00, 506.00/506.01, 507.00, 508.00, 509.00, BMW Longlife-04, Porsche C30, Peugeot Citroën Automobiles B71 2290, B71 2296, B71 2297, B71 2300, B71 2302, B71 2312, B71 2007, B71 2008, Ford WSS-M2C153-H, WSS-M2C930-A, WSS-M2C945-A, WSS-M2C913A, WSS-M2C913-B, WSS-M2C913-C, GM 6094-M, Chrysler MS-6395, or any past or future PCMO or HDD specifications not mentioned herein. In some embodiments for passenger car motor oil (PCMO) applications, the amount of phosphorus in the finished fluid is 1000 ppm or less or 900 ppm or less or 800 ppm or less.

Other hardware may not be suitable for use with the disclosed lubricant. A “functional fluid” is a term which encompasses a variety of fluids including but not limited to tractor hydraulic fluids, power transmission fluids including automatic transmission fluids, continuously variable transmission fluids and manual transmission fluids, hydraulic fluids, including tractor hydraulic fluids, some gear oils, power steering fluids, fluids used in wind turbines, compressors, some industrial fluids, and fluids related to power train components. It should be noted that within each of these fluids such as, for example, automatic transmission fluids, there are a variety of different types of fluids due to the various transmissions having different designs which have led to the need for fluids of markedly different functional characteristics. This is contrasted by the term “lubricating fluid” which is not used to generate or transfer power.

When the functional fluid is an automatic transmission fluid, the automatic transmission fluids must have enough friction for the clutch plates to transfer power. However, the friction coefficient of fluids has a tendency to decline due to the temperature effects as the fluid heats up during operation. It is important that the tractor hydraulic fluid or automatic transmission fluid maintain its high friction coefficient at elevated temperatures, otherwise brake systems or automatic transmissions may fail. This is not a function of an engine oil.

Tractor fluids, and for example Super Tractor Universal Oils (STUOs) or Universal Tractor Transmission Oils (UTTOs), may combine the performance of engine oils with transmissions, differentials, final-drive planetary gears, wet-brakes, and hydraulic performance. While many of the additives used to formulate a UTTO or a STUO fluid are similar in functionality, they may have deleterious effect if not incorporated properly. For example, some anti-wear and extreme pressure additives used in engine oils can be extremely corrosive to the copper components in hydraulic pumps. Detergents and dispersants used for gasoline or diesel engine performance may be detrimental to wet brake performance. Friction modifiers specific to quiet wet brake noise, may lack the thermal stability required for engine oil performance. Each of these fluids, whether functional, tractor, or lubricating, are designed to meet specific and stringent manufacturer requirements.

The present disclosure provides novel lubricating oil blends formulated for use as automotive crankcase lubricants. The present disclosure also provides novel lubricating oil blends formulated for use as 2T and/or 4T motorcycle crankcase lubricants. Embodiments of the present disclosure may provide lubricating oils suitable for crankcase applications and having improvements in the following characteristics: air entrainment, alcohol fuel compatibility, antioxidancy, antiwear performance, biofuel compatibility, foam reducing properties, friction reduction, fuel economy, preignition prevention, rust inhibition, sludge and/or soot dispersability, piston cleanliness, deposit formation, and water tolerance.

Engine oils of the present disclosure may be formulated by the addition of one or more additives, as described in detail below, to an appropriate base oil formulation. The additives may be combined with a base oil in the form of an additive package (or concentrate) or, alternatively, may be combined individually with a base oil (or a mixture of both). The fully formulated engine oil may exhibit improved performance properties, based on the additives added and their respective proportions.

It is to be understood that throughout the present disclosure, the terms “comprises,” “includes,” “contains,” etc. are considered open-ended and include any element, step, or ingredient not explicitly listed. The phrase “consists essentially of” is meant to include any expressly listed element, step, or ingredient and any additional elements, steps, or ingredients that do not materially affect the basic and novel aspects of the invention. The basic and novel aspects of the invention include at least TBN boosting, improving ash content and/or improving ball rust test performance.

The Base Oil

The base oil used in the lubricating oil compositions herein may be selected from any of the base oils in Groups I-V as specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. The five base oil groups are as follows:

TABLE 1 Base oil Saturates Viscosity Category Sulfur (%) (%) Index Group I >0.03 and/or <90 80 to 120 Group II ≦0.03 and ≧90 80 to 120 Group III ≦0.03 and ≧90 ≧120 Group IV All polyalphaolefins (PAOs) Group V All others not included in Groups I, II, III, or IV

Groups I, II, and III are mineral oil process stocks. Group IV base oils contain true synthetic molecular species, which are produced by polymerization of olefinically unsaturated hydrocarbons. Many Group V base oils are also true synthetic products and may include diesters, polyol esters, polyalkylene glycols, alkylated aromatics, polyphosphate esters, polyvinyl ethers, and/or polyphenyl ethers, and the like, but may also be naturally occurring oils, such as vegetable oils. Group IV and V base oils may also contain at least 90% saturates. It should be noted that although Group III base oils are derived from mineral oil, the rigorous processing that these fluids undergo causes their physical properties to be very similar to some true synthetics, such as PAOs. Therefore, oils derived from Group III base oils may be referred to as synthetic fluids in the industry.

The base oil used in the disclosed lubricating oil composition may be a mineral oil, animal oil, vegetable oil, synthetic oil, or mixtures thereof. Suitable oils may be derived from hydrocracking, hydrogenation, hydrofinishing, unrefined, refined, and re-refined oils, and mixtures thereof.

Unrefined oils are those derived from a natural, mineral, or synthetic source without or with little further purification treatment. Refined oils are similar to the unrefined oils except that they have been treated in one or more purification steps, which may result in the improvement of one or more properties. Examples of suitable purification techniques are solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, and the like. Oils refined to the quality of an edible may or may not be useful. Edible oils may also be called white oils. In some embodiments, lubricating oil compositions are free of edible or white oils.

Re-refined oils are also known as reclaimed or reprocessed oils. These oils are obtained similarly to refined oils using the same or similar processes. Often these oils are additionally processed by techniques directed to removal of spent additives and oil breakdown products.

Mineral oils may include oils obtained by drilling or from plants and animals or any mixtures thereof. For example such oils may include, but are not limited to, castor oil, lard oil, olive oil, peanut oil, corn oil, soybean oil, and linseed oil, as well as mineral lubricating oils, such as liquid petroleum oils and solvent-treated or acid-treated mineral lubricating oils of the paraffinic, naphthenic or mixed paraffinic-naphthenic types. Such oils may be partially or fully hydrogenated, if desired. Oils derived from coal or shale may also be useful.

Useful synthetic lubricating oils may include hydrocarbon oils such as polymerized, oligomerized, or interpolymerized olefins (e.g., polybutylenes, polypropylenes, propyleneisobutylene copolymers); poly(1-hexenes), poly(1-octenes), trimers or oligomers of 1-decene, e.g., poly(1-decenes), such materials being often referred to as α-olefins, and mixtures thereof; alkyl-benzenes (e.g. dodecylbenzenes, tetradecylbenzenes, dinonylbenzenes, di-(2-ethylhexyl)-benzenes); polyphenyls (e.g., biphenyls, terphenyls, alkylated polyphenyls); diphenyl alkanes, alkylated diphenyl alkanes, alkylated diphenyl ethers and alkylated diphenyl sulfides and the derivatives, analogs and homologs thereof or mixtures thereof. Polyalphaolefins are typically hydrogenated materials.

Other synthetic lubricating oils include polyol esters, diesters, liquid esters of phosphorus-containing acids (e.g., tricresyl phosphate, trioctyl phosphate, and the diethyl ester of decane phosphoric acid), or polymeric tetrahydrofurans. Synthetic oils may be produced by Fischer-Tropsch reactions and typically may be hydroisomerized Fischer-Tropsch hydrocarbons or waxes. In one embodiment oils may be prepared by a Fischer-Tropsch gas-to-liquid synthetic procedure as well as other gas-to-liquid oils.

The major amount of base oil included in a lubricating composition may be selected from the group consisting of Group I, Group II, a Group III, a Group IV, a Group V, and a combination of two or more of the foregoing, and wherein the major amount of base oil is other than base oils that arise from provision of additive components or viscosity index improvers in the composition. In another embodiment, the major amount of base oil included in a lubricating composition may be selected from the group consisting of Group II, a Group III, a Group IV, a Group V, and a combination of two or more of the foregoing, and wherein the major amount of base oil is other than base oils that arise from provision of additive components or viscosity index improvers in the composition.

The amount of the oil of lubricating viscosity present may be the balance remaining after subtracting from 100 wt % the sum of the amount of the performance additives inclusive of viscosity index improver(s) and/or pour point depressant(s) and/or other top treat additives. For example, the oil of lubricating viscosity that may be present in a finished fluid may be a major amount, such as greater than about 50 wt %, greater than about 60 wt %, greater than about 70 wt %, greater than about 80 wt %, greater than about 85 wt %, or greater than about 90 wt %.

The TBN Boosters

TBN may be measured by several techniques. The most commonly used methods for measuring TBN include ASTM D-2896 and ASTM D-4739. The test method of ASTM D-2896 uses perchloric acid, which is a strong base which makes it most effective for testing TBN of a new oil, since perchloric acid is able to titrate weak bases. However, the TBN value as measured by ASTM D-2896 may produce a falsely exaggerated base number for a used oil due to the presence of one or more components generated by the degradation of the oil over time.

The ASTM D-4739 test method titrates with a weaker acid, hydrochloric acid, which has a lesser tendency to titrate weak bases present in the oil. An additive compound that is capable of boosting TBN as measured by both ASTM D-2896 and ASTM D-4739 is desirable as this gives a better indication of an additive's ability to neutralize any acidic byproducts created during the life of an oil. Thus, the TBN boosters of the present disclosure are selected for their ability to boost the TBN of a lubricating oil as measured by both ASTM D-2896 and ASTM D-4739.

In embodiments of the disclosure, certain guanidines, derivatives of N,N-dimethyl-1,3-propane diamine and compounds of the Formula (VI):

are capable of increasing the TBN of the lubricating oil as measured by ASTM D-4739. Optionally, one or more of the same TBN boosters may also boost the TBN of the lubricating oil as measured by ASTM D-2896. In some other embodiments, these same TBN boosters may improve the performance of the lubricating oil in a Ball Rust Test.

Guanidines

In a first aspect, the disclosure relates to a lubricating oil composition including greater than 50% by weight of a base oil, based on the total weight of the lubricating oil composition and an additive composition comprising a TBN booster selected from one of:

(i) a reaction product of a dicyclohexyl carbodiimide with a primary or a secondary amine, and

(ii) at least one guanidine compound of the Formula (I):

wherein R′, R″, and R′″ are independently selected from the group consisting of a hydrogen, or a hydrocarbyl groups of about 1 to about 50 carbon atoms. Compounds of the Formula (I) may be formed as a reaction product of a dicyclohexyl carbodiimide with a primary or secondary amine. Preferably, the primary amine contains a hydrocarbyl group having 2-20 carbon atoms, more preferably, 6-16 carbon atoms and most preferably 8 to 12 carbon atoms. Preferably, the secondary amine includes two independently selected hydrocarbyl groups each having a total of 2-20 carbon atoms, more preferably, 6-16 carbon atoms and most preferably 8 to 12 carbon atoms.

In some embodiments, the reaction product of the dicyclohexyl carbodiimide with a primary or secondary amine may be used directly as a component of an additive or in a lubricating oil composition

In some embodiments, R′ is hydrocarbyl group having from about 3 to about 30 carbon atoms, or from about 4 to about 15 carbon atoms, or from about 6 to about 12 carbon atoms, and R″ and R′″ are hydrocarbyl groups having from about 4 to about 15 carbon atoms, or about 6 to about 12 carbon atoms. In certain embodiments R′, R″, and R′″ are independently selected from alkyl groups having from about 3 to about 30 carbon atoms, or alkyl groups having from about 4 to about 15 carbon atom, or alkyl groups having from about 6 to about 12 carbon atoms.

In certain embodiments, the lubricating oil composition comprises a reaction product of dicyclohexyl carbodiimide with a primary amine. In other embodiments, the lubricating oil composition comprises a reaction product of dicyclohexyl carbodiimide with a secondary amine.

In certain embodiments, the additive composition comprises a compound of the Formula (I) selected from the group consisting of N-dodecyl-N′N″-dicyclohexylguanidine, N-2-ethylhexyl-N′,N″-dicyclohexylguanidine, N-benzyl-N′,N″-dicyclohexylguanidine, N-cyclohexyl-N′-dicyclohexyl-N″-cyclohexylguanidine, N-oleyl-N′,N″-dicyclohexylguanidin and N,N-dihexyl-N′,N″-dicyclohexylguanidine.

N,N-dimethyl-1,3-propanediamine (DMAPA) Derivatives

In another aspect, the disclosure relates to a lubricating oil composition including greater than 50% by weight of a base oil, based on the total weight of the lubricating oil composition and an additive composition comprising a TBN booster selected from one of:

-   -   (i) a reaction product of a polyamine including at least one         primary amino group and at least one compound of the following         Formulas (II)-(III):

wherein n=50 to 150, R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms and R₂ is selected from hydrogen, or a hydrocarbyl group of 1 to 50 carbon atoms, and the compounds of the Formula (III) have a total number average molecular weight (Mn) of 10,000 to 70,000; and

-   -   (ii) a compound of one of the following Formulas (IV) to (V):

wherein n=50 to 150, R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms, R₂ is selected from hydrogen, or a hydrocarbyl group of 1-50 carbon atoms, and has a total MW of 20,000 to 65,000 and R₇ is an amino group.

The amino group R₇ may be a monoamino group or a polyamino group. The amino group R₇ may be a hydrocarbyl amino group, or, for example, an alkyl amino group, an aryl amino group or an alkaryl amino group. Preferably, R₇ is a hydrocarbyl amino group or an alkyl amino group. More preferably, R₇ is an alkyl amino group having 1-20, more preferably, 2-18, 3-16 or 4-12 carbon atoms.

In certain embodiments, the additive composition comprises the compounds of Formulas (IV) and (V). These compounds of the Formulas (IV)-(V) may be formed as the reaction product of a N,N-dimethyl-1,3-propanediamine and a compound of the Formulae (II)-(III):

wherein n=50 to 150, R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms and R₂ is selected from hydrogen, or a hydrocarbyl group of 1-50 carbon atoms, and the compounds of the Formula (III) have a total molecular weight (Mn) of 10,000 to 70,000; or, more preferably, 20,000 to 60,000, or, most preferably, 30,000 to 50,000.

In certain embodiments R′, R″, and R′″ are independently selected from hydrocarbyl groups having from about 3 to about 30 carbon atoms, or hydrocarbyl groups having from about 4 to about 15 carbon atom, or hydrocarbyl groups having from about 6 to about 12 carbon atoms. In certain embodiments R′, R″, and R′″ are independently selected from alkyl groups having from about 3 to about 30 carbon atoms, or alkyl groups having from about 4 to about 15 carbon atom, or alkyl groups having from about 6 to about 12 carbon atoms.

In another aspect, the disclosure relates to a lubricating oil composition including greater than 50% by weight of a base oil, based on the total weight of the lubricating oil composition and an additive composition comprising a compound of the Formula (VI):

wherein R₆ is a hydrocarbyl group having 1-20 carbon atoms, more preferably, 2-18 carbon atoms and most preferably 4 to 12 carbon atoms.

The amount of the TBN booster that is employed in the lubricating compositions of the present invention is an amount which is sufficient to at least increase the TBN of the lubricating oil composition, as measured by ASTM D-4739. Optionally, one or more of the same TBN boosters may also boost the TBN of the lubricating oil as measured by ASTM D-2896. In some other embodiments, these same TBN boosters may improve the performance of the lubricating oil in a Ball Rust Test.

In the embodiments of the disclosure, the lubricating oil may exhibit an increase in ASTM D-4739 TBN of from about 0.2 to about 2, more preferably, from about 0.4 to about 1.5, or, even more preferably, from about 0.5 to about 1.2, as a result of the addition of the TBN booster. The increase in the TBN is determined relative to a same composition in the absence of component (i) or (ii).

In some embodiments, the amount of the TBN booster ranges from about 0.01 to about 2 wt. %, or from about 0.1 to about 1.8 wt. % or from about 0.25 to about 1.5 wt. % of the reaction product and/or a compound of the Formulae (I) and (IV)-(VII), based on the total weight of the lubricating oil composition.

Detergents

The lubricating oil composition may optionally further comprise one or more neutral, low based, or overbased detergents, and mixtures thereof. Suitable detergent substrates include phenates, sulfur containing phenates, sulfonates, calixarates, salixarates, salicylates, carboxylic acids, phosphorus acids, mono- and/or di-thiophosphoric acids, alkyl phenols, sulfur coupled alkyl phenol compounds, or methylene bridged phenols. Suitable detergents and their methods of preparation are described in greater detail in numerous patent publications, including U.S. Pat. No. 7,732,390 and references cited therein. The detergent substrate may be salted with an alkali or alkaline earth metal such as, but not limited to, calcium, magnesium, potassium, sodium, lithium, barium, or mixtures thereof. In some embodiments, the detergent is free of barium. A suitable detergent may include alkali or alkaline earth metal salts of petroleum sulfonic acids and long chain mono- or di-alkylarylsulfonic acids with the aryl group being benzyl, tolyl, and xylyl. Examples of suitable detergents include, but are not limited to, calcium phenates, calcium sulfur containing phenates, calcium sulfonates, calcium calixarates, calcium salixarates, calcium salicylates, calcium carboxylic acids, calcium phosphorus acids, calcium mono- and/or di-thiophosphoric acids, calcium alkyl phenols, calcium sulfur coupled alkyl phenol compounds, calcium methylene bridged phenols, magnesium phenates, magnesium sulfur containing phenates, magnesium sulfonates, magnesium calixarates, magnesium salixarates, magnesium salicylates, magnesium carboxylic acids, magnesium phosphorus acids, magnesium mono- and/or di-thiophosphoric acids, magnesium alkyl phenols, magnesium sulfur coupled alkyl phenol compounds, magnesium methylene bridged phenols, sodium phenates, sodium sulfur containing phenates, sodium sulfonates, sodium calixarates, sodium salixarates, sodium salicylates, sodium carboxylic acids, sodium phosphorus acids, sodium mono- and/or di-thiophosphoric acids, sodium alkyl phenols, sodium sulfur coupled alkyl phenol compounds, or sodium methylene bridged phenols.

Overbased detergent additives are well known in the art and may be alkali or alkaline earth metal overbased detergent additives. Such detergent additives may be prepared by reacting a metal oxide or metal hydroxide with a substrate and carbon dioxide gas. The substrate is typically an acid, for example, an acid such as an aliphatic substituted sulfonic acid, an aliphatic substituted carboxylic acid, or an aliphatic substituted phenol.

The terminology “overbased” relates to metal salts, such as metal salts of sulfonates, carboxylates, and phenates, wherein the amount of metal present exceeds the stoichiometric amount. Such salts may have a conversion level in excess of 100% (i.e., they may comprise more than 100% of the theoretical amount of metal needed to convert the acid to its “normal,” “neutral” salt). The expression “metal ratio,” often abbreviated as MR, is used to designate the ratio of total chemical equivalents of metal in the overbased salt to chemical equivalents of the metal in a neutral salt according to known chemical reactivity and stoichiometry. In a normal or neutral salt, the metal ratio is one and in an overbased salt, MR, is greater than one. They are commonly referred to as overbased, hyperbased, or superbased salts and may be salts of organic sulfur acids, carboxylic acids, or phenols.

An overbased detergent of the lubricating oil composition may have a total base number (TBN) of about 200 mg KOH/gram of sample or greater, or as further examples, about 250 mg KOH/gram of sample or greater, or about 350 mg KOH/gram of sample or greater, or about 375 mg KOH/gram of sample or greater, or about 400 mg KOH/gram of sample or greater.

Examples of suitable overbased detergents include, but are not limited to, overbased calcium phenates, overbased calcium sulfur containing phenates, overbased calcium sulfonates, overbased calcium calixarates, overbased calcium salixarates, overbased calcium salicylates, overbased calcium carboxylic acids, overbased calcium phosphorus acids, overbased calcium mono- and/or di-thiophosphoric acids, overbased calcium alkyl phenols, overbased calcium sulfur coupled alkyl phenol compounds, overbased calcium methylene bridged phenols, overbased magnesium phenates, overbased magnesium sulfur containing phenates, overbased magnesium sulfonates, overbased magnesium calixarates, overbased magnesium salixarates, overbased magnesium salicylates, overbased magnesium carboxylic acids, overbased magnesium phosphorus acids, overbased magnesium mono- and/or di-thiophosphoric acids, overbased magnesium alkyl phenols, overbased magnesium sulfur coupled alkyl phenol compounds, or overbased magnesium methylene bridged phenols.

The overbased detergent may have a metal to substrate ratio of from 1.1:1, or from 2:1, or from 4:1, or from 5:1, or from 7:1, or from 10:1.

In some embodiments, a detergent is effective at reducing or preventing rust in an engine.

The detergent may be present at about 0 wt % to about 10 wt %, or about 0.1 wt % to about 8 wt %, or about 1 wt % to about 4 wt %, or greater than about 4 wt % to about 8 wt %.

The total overbased calcium detergent content delivered to the lubricating oil composition may be no more than 3 wt. %, more preferably no more than 2 wt. %, and even more preferably no more than 1.1 wt. %, based on the total weight of the lubricating oil composition.

The overbased detergent may have a metal to substrate ratio of from 1.1:1, or from 2:1, or from 4:1, or from 5:1, or from 7:1, or from 10:1. In some embodiments, a detergent is effective at reducing or preventing rust in an engine.

Antioxidants

The lubricating oil compositions herein also may optionally contain one or more antioxidants. Antioxidant compounds are known and include for example, phenates, phenate sulfides, sulfurized olefins, phosphosulfurized terpenes, sulfurized esters, aromatic amines, alkylated diphenylamines (e.g., nonyl diphenylamine, di-nonyl diphenylamine, octyl diphenylamine, di-octyl diphenylamine), phenyl-alpha-naphthylamines, alkylated phenyl-alpha-naphthylamines, hindered non-aromatic amines, phenols, hindered phenols, oil-soluble molybdenum compounds, macromolecular antioxidants, or mixtures thereof. Antioxidant compounds may be used alone or in combination.

The hindered phenol antioxidant may contain a secondary butyl and/or a tertiary butyl group as a sterically hindering group. The phenol group may be further substituted with a hydrocarbyl group and/or a bridging group linking to a second aromatic group. Examples of suitable hindered phenol antioxidants include 2,6-di-tert-butylphenol, 4-methyl-2,6-di-tert-butylphenol, 4-ethyl-2,6-di-tert-butylphenol, 4-propyl-2,6-di-tert-butylphenol or 4-butyl-2,6-di-tert-butylphenol, or 4-dodecyl-2,6-di-tert-butylphenol. In one embodiment the hindered phenol antioxidant may be an ester and may include, e.g., Irganox™ L-135 available from BASF or an addition product derived from 2,6-di-tert-butylphenol and an alkyl acrylate, wherein the alkyl group may contain about 1 to about 18, or about 2 to about 12, or about 2 to about 8, or about 2 to about 6, or about 4 carbon atoms. Another commercially available hindered phenol antioxidant may be an ester and may include Ethanox™ 4716 available from Albemarle Corporation.

Useful antioxidants may include diarylamines and high molecular weight phenols. In an embodiment, the lubricating oil composition may contain a mixture of a diarylamine and a high molecular weight phenol, such that each antioxidant may be present in an amount sufficient to provide up to about 5%, by weight, based upon the final weight of the lubricating oil composition. In an embodiment, the antioxidant may be a mixture of about 0.3 to about 1.5% diarylamine and about 0.4 to about 2.5% high molecular weight phenol, by weight, based upon the final weight of the lubricating oil composition.

Examples of suitable olefins that may be sulfurized to form a sulfurized olefin include propylene, butylene, isobutylene, polyisobutylene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecene, tridecene, tetradecene, pentadecene, hexadecene, heptadecene, octadecene, nonadecene, eicosene or mixtures thereof. In one embodiment, hexadecene, heptadecene, octadecene, nonadecene, eicosene or mixtures thereof and their dimers, trimers and tetramers are especially useful olefins. Alternatively, the olefin may be a Diels-Alder adduct of a diene such as 1,3-butadiene and an unsaturated ester, such as, butylacrylate.

Another class of sulfurized olefin includes sulfurized fatty acids and their esters. The fatty acids are often obtained from vegetable oil or animal oil and typically contain about 4 to about 22 carbon atoms. Examples of suitable fatty acids and their esters include triglycerides, oleic acid, linoleic acid, palmitoleic acid or mixtures thereof. Often, the fatty acids are obtained from lard oil, tall oil, peanut oil, soybean oil, cottonseed oil, sunflower seed oil or mixtures thereof. Fatty acids and/or ester may be mixed with olefins, such as α-olefins.

The one or more antioxidant(s) may be present in ranges about 0 wt % to about 20 wt %, or about 0.1 wt % to about 10 wt %, or about 1 wt % to about 5 wt %, of the lubricating oil composition.

Antiwear Agents

The lubricating oil compositions herein also may optionally contain one or more antiwear agents. Examples of suitable antiwear agents include, but are not limited to, a metal thiophosphate; a metal dialkyldithiophosphate; a phosphoric acid ester or salt thereof; a phosphate ester(s); a phosphite; a phosphorus-containing carboxylic ester, ether, or amide; a sulfurized olefin; thiocarbamate-containing compounds including, thiocarbamate esters, alkylene-coupled thiocarbamates, and bis(S-alkyldithiocarbamyl)disulfides; and mixtures thereof. A suitable antiwear agent may be a molybdenum dithiocarbamate. The phosphorus containing antiwear agents are more fully described in European Patent 612 839. The metal in the dialkyl dithio phosphate salts may be an alkali metal, alkaline earth metal, aluminum, lead, tin, molybdenum, manganese, nickel, copper, titanium, or zinc. A useful antiwear agent may be zinc dialkylthiophosphate.

Further examples of suitable antiwear agents include titanium compounds, tartrates, tartrimides, oil soluble amine salts of phosphorus compounds, sulfurized olefins, phosphites (such as dibutyl phosphite), phosphonates, thiocarbamate-containing compounds, such as thiocarbamate esters, thiocarbamate amides, thiocarbamic ethers, alkylene-coupled thiocarbamates, and bis(S-alkyldithiocarbamyl) disulfides. The tartrate or tartrimide may contain alkyl-ester groups, where the sum of carbon atoms on the alkyl groups may be at least 8. The antiwear agent may in one embodiment include a citrate.

The antiwear agent may be present in ranges including about 0 wt % to about 15 wt %, or about 0.01 wt % to about 10 wt %, or about 0.05 wt % to about 5 wt %, or about 0.1 wt % to about 3 wt % of the lubricating oil composition.

Boron Containing Agents

The lubricating oil compositions herein may optionally contain one or more boron-containing compounds.

Examples of boron-containing compounds include borate esters, borated fatty amines, borated epoxides, borated detergents, and borated dispersants, such as borated succinimide dispersants, as disclosed in U.S. Pat. No. 5,883,057.

The boron-containing compound, if present, can be used in an amount sufficient to provide up to about 8 wt %, about 0.01 wt % to about 7 wt %, about 0.05 wt % to about 5 wt %, or about 0.1 wt % to about 3 wt % of the lubricating oil composition.

Dispersants

The lubricating oil composition may optionally further comprise one or more dispersants or mixtures thereof. Dispersants are often known as ashless-type dispersants because, prior to mixing in a lubricating oil composition, they do not contain ash-forming metals and they do not normally contribute any ash when added to a lubricant. Ashless type dispersants are characterized by a polar group attached to a relatively high molecular weight hydrocarbon chain. Typical ashless dispersants include N-substituted long chain alkenyl succinimides. Examples of N-substituted long chain alkenyl succinimides include polyisobutylene succinimide with number average molecular weight of the polyisobutylene substituent in the range about 350 to about 50,000, or to about 5,000, or to about 3,000. Succinimide dispersants and their preparation are disclosed, for instance in U.S. Pat. No. 7,897,696 or U.S. Pat. No. 4,234,435. The polyolefin may be prepared from polymerizable monomers containing about 2 to about 16, or about 2 to about 8, or about 2 to about 6 carbon atoms. Succinimide dispersants are typically the imide formed from a polyamine, typically a poly(ethyleneamine).

In an embodiment the present disclosure further comprises at least one polyisobutylene succinimide dispersant derived from polyisobutylene with number average molecular weight in the range about 350 to about 50,000, or to about 5000, or to about 3000. The polyisobutylene succinimide may be used alone or in combination with other dispersants.

In some embodiments, polyisobutylene, when included, may have greater than 50 mol %, greater than 60 mol %, greater than 70 mol %, greater than 80 mol %, or greater than 90 mol % content of terminal double bonds. Such PIB is also referred to as highly reactive PIB (“HR-PIB”). HR-PIB having a number average molecular weight ranging from about 800 to about 5000 is suitable for use in embodiments of the present disclosure. Conventional PIB typically has less than 50 mol %, less than 40 mol %, less than 30 mol %, less than 20 mol %, or less than 10 mol % content of terminal double bonds.

An HR-PIB having a number average molecular weight ranging from about 900 to about 3000 may be suitable. Such HR-PIB is commercially available, or can be synthesized by the polymerization of isobutene in the presence of a non-chlorinated catalyst such as boron trifluoride, as described in U.S. Pat. No. 4,152,499 to Boerzel, et al. and U.S. Pat. No. 5,739,355 to Gateau, et al. When used in the aforementioned thermal ene reaction, HR-PIB may lead to higher conversion rates in the reaction, as well as lower amounts of sediment formation, due to increased reactivity. A suitable method is described in U.S. Pat. No. 7,897,696.

In one embodiment the present disclosure further comprises at least one dispersant derived from polyisobutylene succinic anhydride (“PIBSA”). The PIBSA may have an average of between about 1.0 and about 2.0 succinic acid moieties per polymer.

The % actives of the alkenyl or alkyl succinic anhydride can be determined using a chromatographic technique. This method is described in column 5 and 6 in U.S. Pat. No. 5,334,321. The percent conversion of the polyolefin is calculated from the % actives using the equation in column 5 and 6 in U.S. Pat. No. 5,334,321.

Unless stated otherwise, all percentages are in weight percent and all molecular weights are number average molecular weights.

In one embodiment, the dispersant may be derived from a polyalphaolefin (PAO) succinic anhydride.

In one embodiment, the dispersant may be derived from olefin maleic anhydride copolymer. As an example, the dispersant may be described as a poly-PIBSA.

In an embodiment, the dispersant may be derived from an anhydride which is grafted to an ethylene-propylene copolymer.

One class of suitable dispersants may be Mannich bases. Mannich bases are materials that are formed by the condensation of a higher molecular weight, alkyl substituted phenol, a polyalkylene polyamine, and an aldehyde such as formaldehyde. Mannich bases are described in more detail in U.S. Pat. No. 3,634,515.

A suitable class of dispersants may be high molecular weight esters or half ester amides.

A suitable dispersant may also be post-treated by conventional methods by a reaction with any of a variety of agents. Among these are boron, urea, thiourea, dimercaptothiadiazoles, carbon disulfide, aldehydes, ketones, carboxylic acids, anhydrides, hydrocarbon-substituted succinic anhydrides, nitriles, epoxides, carbonates, cyclic carbonates, hindered phenolic esters, and phosphorus compounds. U.S. Pat. No. 7,645,726; U.S. Pat. No. 7,214,649; and U.S. Pat. No. 8,048,831 disclose exemplary suitable post-treatments.

In addition to the carbonate and boric acids post-treatments both the compounds may be post-treated, or further post-treatment, with a variety of post-treatments designed to improve or impart different properties. Such post-treatments include those summarized in columns 27-29 of U.S. Pat. No. 5,241,003.

The TBN of a suitable dispersant may be from about 10 to about 65 on an oil-free basis, which is comparable to about 5 to about 30 TBN if measured on a dispersant sample containing about 50% diluent oil.

The dispersant, if present, can be used in an amount sufficient to provide up to about 20 wt %, based upon the final weight of the lubricating oil composition. Another amount of the dispersant that can be used may be about 0.1 wt % to about 15 wt %, or about 0.1 wt % to about 10 wt %, or about 3 wt % to about 10 wt %, or about 1 wt % to about 6 wt %, or about 7 wt % to about 12 wt %, based upon the final weight of the lubricating oil composition. In some embodiments, the lubricating oil composition utilizes a mixed dispersant system. A single type or a mixture of two or more types of dispersants in any desired ratio may be used.

Extreme Pressure Agents

The lubricating oil compositions herein also may optionally contain one or more extreme pressure agents. Extreme Pressure (EP) agents that are soluble in the oil include sulfur- and chlorosulfur-containing EP agents, chlorinated hydrocarbon EP agents and phosphorus EP agents. Examples of such EP agents include chlorinated wax; organic sulfides and polysulfides such as dibenzyldisulfide, bis(chlorobenzyl) disulfide, dibutyl tetrasulfide, sulfurized methyl ester of oleic acid, sulfurized alkylphenol, sulfurized dipentene, sulfurized terpene, and sulfurized Diels-Alder adducts; phosphosulfurized hydrocarbons such as the reaction product of phosphorus sulfide with turpentine or methyl oleate; phosphorus esters such as the dihydrocarbyl and trihydrocarbyl phosphites, e.g., dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, pentylphenyl phosphite; dipentylphenyl phosphite, tridecyl phosphite, distearyl phosphite and polypropylene substituted phenyl phosphite; metal thiocarbamates such as zinc dioctyldithiocarbamate and barium heptylphenol diacid; amine salts of alkyl and dialkylphosphoric acids, including, for example, the amine salt of the reaction product of a dialkyldithiophosphoric acid with propylene oxide; and mixtures thereof.

Friction Modifiers

The lubricating oil compositions herein also may optionally contain one or more friction modifiers. Suitable friction modifiers may comprise metal containing and metal-free friction modifiers and may include, but are not limited to, imidazolines, amides, amines, succinimides, alkoxylated amines, alkoxylated ether amines, amine oxides, amidoamines, nitriles, betaines, quaternary amines, imines, amine salts, amino guanadine, alkanolamides, phosphonates, metal-containing compounds, glycerol esters, sulfurized fatty compounds and olefins, sunflower oil other naturally occurring plant or animal oils, dicarboxylic acid esters, esters or partial esters of a polyol and one or more aliphatic or aromatic carboxylic acids, and the like.

Suitable friction modifiers may contain hydrocarbyl groups that are selected from straight chain, branched chain, or aromatic hydrocarbyl groups or mixtures thereof, and may be saturated or unsaturated. The hydrocarbyl groups may be composed of carbon and hydrogen or hetero atoms such as sulfur or oxygen. The hydrocarbyl groups may range from about 12 to about 25 carbon atoms. In some embodiments the friction modifier may be a long chain fatty acid ester. In another embodiment the long chain fatty acid ester may be a mono-ester, or a di-ester, or a (tri)glyceride. The friction modifier may be a long chain fatty amide, a long chain fatty ester, a long chain fatty epoxide derivatives, or a long chain imidazoline.

Other suitable friction modifiers may include organic, ashless (metal-free), nitrogen-free organic friction modifiers. Such friction modifiers may include esters formed by reacting carboxylic acids and anhydrides with alkanols and generally include a polar terminal group (e.g. carboxyl or hydroxyl) covalently bonded to an oleophilic hydrocarbon chain. An example of an organic ashless nitrogen-free friction modifier is known generally as glycerol monooleate (GMO) which may contain mono-, di-, and tri-esters of oleic acid. Other suitable friction modifiers are described in U.S. Pat. No. 6,723,685.

Aminic friction modifiers may include amines or polyamines. Such compounds can have hydrocarbyl groups that are linear, either saturated or unsaturated, or a mixture thereof and may contain from about 12 to about 25 carbon atoms. Further examples of suitable friction modifiers include alkoxylated amines and alkoxylated ether amines. Such compounds may have hydrocarbyl groups that are linear, either saturated, unsaturated, or a mixture thereof. They may contain from about 12 to about 25 carbon atoms. Examples include ethoxylated amines and ethoxylated ether amines.

The amines and amides may be used as such or in the form of an adduct or reaction product with a boron compound such as a boric oxide, boron halide, metaborate, boric acid or a mono-, di- or tri-alkyl borate. Other suitable friction modifiers are described in U.S. Pat. No. 6,300,291.

A friction modifier may optionally be present in ranges such as about 0 wt % to about 10 wt %, or about 0.01 wt % to about 8 wt %, or about 0.1 wt % to about 4 wt %.

Molybdenum-Containing Component

The lubricating oil compositions herein also may optionally contain one or more molybdenum-containing compounds. An oil-soluble molybdenum compound may have the functional performance of an antiwear agent, an antioxidant, a friction modifier, or mixtures thereof. An oil-soluble molybdenum compound may include molybdenum dithiocarbamates, molybdenum dialkyldithiophosphates, molybdenum dithiophosphinates, amine salts of molybdenum compounds, molybdenum xanthates, molybdenum thioxanthates, molybdenum sulfides, molybdenum carboxylates, molybdenum alkoxides, a trinuclear organo-molybdenum compound, and/or mixtures thereof. The molybdenum sulfides include molybdenum disulfide. The molybdenum disulfide may be in the form of a stable dispersion. In one embodiment the oil-soluble molybdenum compound may be selected from the group consisting of molybdenum dithiocarbamates, molybdenum dialkyldithiophosphates, amine salts of molybdenum compounds, and mixtures thereof. In one embodiment the oil-soluble molybdenum compound may be a molybdenum dithiocarbamate.

Suitable examples of molybdenum compounds which may be used include commercial materials sold under the trade names such as Molyvan 822™, Molyvan™ A, Molyvan 2000™ and Molyvan 855™ from R. T. Vanderbilt Co., Ltd., and Sakura-Lube™ S-165, S-200, S-300, S-310G, S-525, S-600, S-700, and S-710 available from Adeka Corporation, and mixtures thereof. Suitable molybdenum components are described in U.S. Pat. No. 5,650,381; U.S. RE 37,363 E1; U.S. RE 38,929 E1; and U.S. RE 40,595 E1.

Additionally, the molybdenum compound may be an acidic molybdenum compound. Included are molybdic acid, ammonium molybdate, sodium molybdate, potassium molybdate, and other alkaline metal molybdates and other molybdenum salts, e.g., hydrogen sodium molybdate, MoOCl4, MoO2Br2, Mo2O3Cl6, molybdenum trioxide or similar acidic molybdenum compounds. Alternatively, the compositions can be provided with molybdenum by molybdenum/sulfur complexes of basic nitrogen compounds as described, for example, in U.S. Pat. Nos. 4,263,152; 4,285,822; 4,283,295; 4,272,387; 4,265,773; 4,261,843; 4,259,195 and 4,259,194; and WO 94/06897.

Another class of suitable organo-molybdenum compounds are trinuclear molybdenum compounds, such as those of the formula Mo3SkLnQz and mixtures thereof, wherein S represents sulfur, L represents independently selected ligands having organo groups with a sufficient number of carbon atoms to render the compound soluble or dispersible in the oil, n is from 1 to 4, k varies from 4 through 7, Q is selected from the group of neutral electron donating compounds such as water, amines, alcohols, phosphines, and ethers, and z ranges from 0 to 5 and includes non-stoichiometric values. At least 21 total carbon atoms may be present among all the ligands' organo groups, such as at least 25, at least 30, or at least 35 carbon atoms. Additional suitable molybdenum compounds are described in U.S. Pat. No. 6,723,685.

The oil-soluble molybdenum compound may be present in an amount sufficient to provide about 0.5 ppm to about 2000 ppm, about 1 ppm to about 700 ppm, about 1 ppm to about 550 ppm, about 5 ppm to about 300 ppm, or about 20 ppm to about 250 ppm of molybdenum.

Transition Metal-Containing Compounds

In another embodiment, the oil-soluble compound may be a transition metal containing compound or a metalloid. The transition metals may include, but are not limited to, titanium, vanadium, copper, zinc, zirconium, molybdenum, tantalum, tungsten, and the like. Suitable metalloids include, but are not limited to, boron, silicon, antimony, tellurium, and the like.

In an embodiment, an oil-soluble transition metal-containing compound may function as antiwear agents, friction modifiers, antioxidants, deposit control additives, or more than one of these functions. In an embodiment the oil-soluble transition metal-containing compound may be an oil-soluble titanium compound, such as a titanium (IV) alkoxide. Among the titanium containing compounds that may be used in, or which may be used for preparation of the oils-soluble materials of, the disclosed technology are various Ti (IV) compounds such as titanium (IV) oxide; titanium (IV) sulfide; titanium (IV) nitrate; titanium (IV) alkoxides such as titanium methoxide, titanium ethoxide, titanium propoxide, titanium isopropoxide, titanium butoxide, titanium 2-ethylhexoxide; and other titanium compounds or complexes including but not limited to titanium phenates; titanium carboxylates such as titanium (IV) 2-ethyl-1-3-hexanedioate or titanium citrate or titanium oleate; and titanium (IV) (triethanolaminato)isopropoxide. Other forms of titanium encompassed within the disclosed technology include titanium phosphates such as titanium dithiophosphates (e.g., dialkyldithiophosphates) and titanium sulfonates (e.g., alkylbenzenesulfonates), or, generally, the reaction product of titanium compounds with various acid materials to form salts, such as oil-soluble salts. Titanium compounds can thus be derived from, among others, organic acids, alcohols, and glycols. Ti compounds may also exist in dimeric or oligomeric form, containing Ti—O—Ti structures. Such titanium materials are commercially available or can be readily prepared by appropriate synthesis techniques which will be apparent to the person skilled in the art. They may exist at room temperature as a solid or a liquid, depending on the particular compound. They may also be provided in a solution form in an appropriate inert solvent.

In one embodiment, the titanium can be supplied as a Ti-modified dispersant, such as a succinimide dispersant. Such materials may be prepared by forming a titanium mixed anhydride between a titanium alkoxide and a hydrocarbyl-substituted succinic anhydride, such as an alkenyl- (or alkyl) succinic anhydride. The resulting titanate-succinate intermediate may be used directly or it may be reacted with any of a number of materials, such as (a) a polyamine-based succinimide/amide dispersant having free, condensable —NH functionality; (b) the components of a polyamine-based succinimide/amide dispersant, i.e., an alkenyl- (or alkyl-) succinic anhydride and a polyamine, (c) a hydroxy-containing polyester dispersant prepared by the reaction of a substituted succinic anhydride with a polyol, aminoalcohol, polyamine, or mixtures thereof. Alternatively, the titanate-succinate intermediate may be reacted with other agents such as alcohols, aminoalcohols, ether alcohols, polyether alcohols or polyols, or fatty acids, and the product thereof either used directly to impart Ti to a lubricant, or else further reacted with the succinic dispersants as described above. As an example, 1 part (by mole) of tetraisopropyl titanate may be reacted with about 2 parts (by mole) of a polyisobutene-substituted succinic anhydride at 140-150° C. for 5 to 6 hours to provide a titanium modified dispersant or intermediate. The resulting material (30 g) may be further reacted with a succinimide dispersant from polyisobutene-substituted succinic anhydride and a polyethylenepolyamine mixture (127 grams+diluent oil) at 150° C. for 1.5 hours, to produce a titanium-modified succinimide dispersant.

Another titanium containing compound may be a reaction product of titanium alkoxide and C₆ to C₂₅ carboxylic acid. The reaction product may be represented by the following formula:

wherein n is an integer selected from 2, 3 and 4, and R is a hydrocarbyl group containing from about 5 to about 24 carbon atoms, or by the formula:

wherein each of R¹, R², R³, and R⁴ are the same or different and are selected from a hydrocarbyl group containing from about 5 to about 25 carbon atoms. Suitable carboxylic acids may include, but are not limited to caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, oleic acid, erucic acid, linoleic acid, linolenic acid, cyclohexanecarboxylic acid, phenylacetic acid, benzoic acid, neodecanoic acid, and the like.

In an embodiment the oil soluble titanium compound may be present in the lubricating oil composition in an amount to provide from 0 to 3000 ppm titanium by weight or 25 to about 1500 ppm titanium by weight or about 35 ppm to 500 ppm titanium by weight or about 50 ppm to about 300 ppm.

Viscosity Index Improvers

The lubricating oil compositions herein also may optionally contain one or more viscosity index improvers. Suitable viscosity index improvers may include polyolefins, olefin copolymers, ethylene/propylene copolymers, polyisobutenes, hydrogenated styrene-isoprene polymers, styrene/maleic ester copolymers, hydrogenated styrene/butadiene copolymers, hydrogenated isoprene polymers, alpha-olefin maleic anhydride copolymers, polymethacrylates, polyacrylates, polyalkyl styrenes, hydrogenated alkenyl aryl conjugated diene copolymers, or mixtures thereof. Viscosity index improvers may include star polymers and suitable examples are described in US Publication No. 20120101017A1.

The lubricating oil compositions herein also may optionally contain one or more dispersant viscosity index improvers in addition to a viscosity index improver or in lieu of a viscosity index improver. Suitable viscosity index improvers may include functionalized polyolefins, for example, ethylene-propylene copolymers that have been functionalized with the reaction product of an acylating agent (such as maleic anhydride) and an amine; polymethacrylates functionalized with an amine, or esterified maleic anhydride-styrene copolymers reacted with an amine.

The total amount of viscosity index improver and/or dispersant viscosity index improver may be about 0 wt % to about 20 wt %, about 0.1 wt % to about 15 wt %, about 0.1 wt % to about 12 wt %, or about 0.5 wt % to about 10 wt %, of the lubricating oil composition.

Other Optional Additives

Other additives may be selected to perform one or more functions required of a lubricating fluid. Further, one or more of the mentioned additives may be multi-functional and provide functions in addition to or other than the function prescribed herein.

A lubricating oil composition according to the present disclosure may optionally comprise other performance additives. The other performance additives may be in addition to specified additives of the present disclosure and/or may comprise one or more of metal deactivators, viscosity index improvers, detergents, ashless TBN boosters, friction modifiers, antiwear agents, corrosion inhibitors, rust inhibitors, dispersants, dispersant viscosity index improvers, extreme pressure agents, antioxidants, foam inhibitors, demulsifiers, emulsifiers, pour point depressants, seal swelling agents and mixtures thereof. Typically, fully-formulated lubricating oil will contain one or more of these performance additives.

Suitable metal deactivators may include derivatives of benzotriazoles (typically tolyltriazole), dimercaptothiadiazole derivatives, 1,2,4-triazoles, benzimidazoles, 2-alkyldithiobenzimidazoles, or 2-alkyldithiobenzothiazoles; foam inhibitors including copolymers of ethyl acrylate and 2-ethylhexylacrylate and optionally vinyl acetate; demulsifiers including trialkyl phosphates, polyethylene glycols, polyethylene oxides, polypropylene oxides and (ethylene oxide-propylene oxide) polymers; pour point depressants including esters of maleic anhydride-styrene, polymethacrylates, polyacrylates or polyacrylamides.

Suitable foam inhibitors include silicon-based compounds, such as siloxane.

Suitable pour point depressants may include a polymethylmethacrylates or mixtures thereof. Pour point depressants may be present in an amount sufficient to provide from about 0 wt % to about 1 wt %, about 0.01 wt % to about 0.5 wt %, or about 0.02 wt % to about 0.04 wt % based upon the final weight of the lubricating oil composition.

Suitable rust inhibitors may be a single compound or a mixture of compounds having the property of inhibiting corrosion of ferrous metal surfaces. Non-limiting examples of rust inhibitors useful herein include oil-soluble high molecular weight organic acids, such as 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, behenic acid, and cerotic acid, as well as oil-soluble polycarboxylic acids including dimer and trimer acids, such as those produced from tall oil fatty acids, oleic acid, and linoleic acid. Other suitable corrosion inhibitors include long-chain alpha, omega-dicarboxylic acids in the molecular weight range of about 600 to about 3000 and alkenylsuccinic acids in which the alkenyl group contains about 10 or more carbon atoms such as, tetrapropenylsuccinic acid, tetradecenylsuccinic acid, and hexadecenylsuccinic acid. Another useful type of acidic corrosion inhibitors are the half esters of alkenyl succinic acids having about 8 to about 24 carbon atoms in the alkenyl group with alcohols such as the polyglycols. The corresponding half amides of such alkenyl succinic acids are also useful. A useful rust inhibitor is a high molecular weight organic acid. In some embodiments, an engine oil is devoid of a rust inhibitor.

The rust inhibitor, if present, can be used in an amount sufficient to provide about 0 wt % to about 5 wt %, about 0.01 wt % to about 3 wt %, about 0.1 wt % to about 2 wt %, based upon the final weight of the lubricating oil composition.

In general terms, a suitable crankcase lubricant may include additive components in the ranges listed in the following table.

TABLE 2 Wt. % Wt. % Suitable Preferred Component Embodiments Embodiments Dispersant(s)  0.1-10.0 1.0-8.5 Antioxidant(s) 0.1-5.0 0.01-3.0  Detergent(s)  0.1-15.0 0.2-8.0 Ashless TBN booster(s) 0.0-1.0 0.01-0.5  Corrosion inhibitor(s) 0.0-5.0 0.0-2.0 Metal dihydrocarbyldithiophosphate(s) 0.1-6.0 0.1-4.0 Ash-free phosphorus compound(s) 0.0-6.0 0.0-4.0 Antifoaming agent(s) 0.0-5.0 0.001-0.15  Antiwear agent(s) 0.0-1.0 0.0-0.8 Pour point depressant(s) 0.0-5.0 0.01-1.5  Viscosity index improver(s)  0.0-20.0 0.25-10.0 Dispersant viscosity index improver(s)  0.0-10.0 0.0-5.0 Friction modifier(s) 0.01-5.0  0.05-2.0  Base oil(s) Balance Balance Total 100 100

The percentages of each component above represent the weight percent of each component, based upon the weight of the final lubricating oil composition. The remainder of the lubricating oil composition consists of one or more base oils.

Additives used in formulating the compositions described herein may be blended into the base oil individually or in various sub-combinations. However, it may be suitable to blend all of the components concurrently using an additive concentrate (i.e., additives plus a diluent, such as a hydrocarbon solvent).

In another embodiment, the disclosure relates to a method of boosting TBN as measured by both ASTM D-2896 and ASTM D-4739. The method includes the step of adding to a lubricating oil any of the TBN boosting reaction products or the compounds of the formulae (I) and (IV)-VII). In certain embodiments, the boosted TBN is determined relative to a same composition in the absence of the TBN booster.

In the method of the invention, the amount of TBN booster added is sufficient such that the lubricating oil exhibits an increase in ASTM D-4739 TBN of from about 0.2 to about 2, more preferably, from about 0.4 to about 1.5, or, even more preferably, from about 0.5 to about 1.2, as a result of the addition of the TBN booster. The increase in the TBN is determined relative to a same composition in the absence of component (i) or (ii).

In some embodiments of the method, the amount of the TBN booster that is employed ranges from about 0.01 to about 2 wt. %, or from about 0.1 to about 1.8 wt. % or from about 0.25 to about 1.5 wt. % of the reaction product and/or a compound of the Formulae (I) and (IV)-(VII), based on the total weight of the lubricating oil composition.

In another embodiment, the disclosure relates to a method of boosting performance in a Ball Rust Test, comprising the step of adding to a lubricating oil composition any of the foregoing TBN boosting reaction products or the TBN boosting compounds of the formulae (I) and (IV)-VI). The performance of the Ball Rust Test is determined relative to a same composition in the absence of the reaction product(s) or the compound(s) of the formulae (I) and (IV)-VI).

In another aspect, the methods of the present invention may maintain, reduce or improve the elongation ratio and tensile strength of seals exposed to the fully formulated lubricating oils used in the methods of the invention.

Additional features and advantages of the disclosure may be set forth in part in the description which follows, and/or may be learned by practice of the disclosure. The features and advantages of the disclosure may be further realized and attained by means of the elements and combinations particularly pointed out in the appended claims.

EXAMPLES

The following examples are illustrative, but not limiting, of the methods and compositions of the present disclosure. Other suitable modifications and adaptations of the variety of conditions and parameters normally encountered in the field, and which are obvious to those skilled in the art, are within the spirit and scope of the disclosure.

Comparative Example A

The TBN of a fully formulated lubricating oil composition containing no TBN booster of the present disclosure and 1.3 wt. % calcium sulfonate detergent based on the total weight of the lubricating composition was measured by both ASTM D-2896 and ASTM D-4739 for comparative purposes.

Comparative Example B

The TBN of a fully formulated lubricating oil composition containing no TBN booster of the present disclosure and 1.1 wt. % calcium sulfonate detergent based on the total weight of the lubricating composition was measured by ASTM D-2896 and ASTM D-4739 for comparative purposes.

Comparative Example C

The fully formulated lubricating oil composition of Example B was evaluated using a Ball Rust Test to measure the corrosion, and the elongation ratio and tensile strength of seals exposed to the fully formulated lubricating oil was also evaluated.

Comparative Example D

Butyl-4-amino benzoate was mixed with a fully formulated lubricant to make up 0.24 wt. %, based on the total weight of the fully formulated lubricant composition, and the TBN was measured by ASTM D-2896 and ASTM D-4739. Butyl-4-amino benzoate has the following structure:

This example demonstrates that not all compounds that boost TBN as measured by ASTM D-2896 also boost TBN as measured by ASTM D-4739.

Example 1

A guanidine compound of the Formula (I) was prepared by reaction of a dicyclohexyl carbodiimide with a dodecylamine using the process as described in U.S. Pat. No. 8,420,761 B The guanidine produced by this reaction product has the following structure:

as well as structural isomers thereof known to skilled persons.

The guanidine product was mixed with a fully formulated lubricating oil to provide a fully formulated lubricant composition containing 0.52 wt. % of the guanidine compound, based on total weight of the lubricating composition, was then mixed with a fully formulated lubricating oil and the TBN was measured by ASTM D-2896 and ASTM D-4739.

Example 2

The guanidine compound as prepared in Example 1 was mixed with a fully formulated lubricating oil to provide a fully formulated lubricant composition containing 0.39 wt. % of the guanidine compound, based on the total weight of the lubricating composition, and the TBN was measured by ASTM D-2896 and ASTM D-4739.

Example 3

The guanidine compound as prepared in Example 1 was mixed with a fully formulated lubricating oil to provide a fully formulated lubricant composition containing 0.65 wt. % of the guanidine compound, based on the total weight of the lubricating composition, and the TBN was measured by ASTM D-2896 and ASTM D-4739.

Example 4

The guanidine compound of Formula (I), can be prepared from dicyclohexyl carbodiimide with a 2-ethylhexylamine using the process described in Example 1. The guanidine produced by this reaction product has the following structure:

This guanidine product was then mixed with a fully formulated lubricant to provide 0.44 wt. % of the guanidine product in the fully formulated lubricant composition, based on the total weight of the fully formulated lubricant composition and the TBN was measured by ASTM D-2896 and ASTM D-4739.

Example 5

The guanidine compound of Formula (I) can be prepared from dicyclohexyl carbodiimide with a benzyl amine using the process described in Example 1. The guanidine produced by the reaction product has the following structure:

The guanidine product was then mixed with a fully formulated lubricant to provide 0.50 wt. % of the guanidine product in the fully formulated lubricant composition, based on the total weight of the fully formulated lubricant composition, and the TBN was measured by ASTM D-2896 and ASTM D-4739.

Example 6

The DMAPA compound of Formula (II), can be prepared by reacting maleic anhydride with a N,N-dimethyl-1,3-propanediamine using the process described in Example 1. The product has the following structure:

This DMAPA product was then mixed with a fully formulated lubricant to provide a fully formulated lubricant composition containing 0.5 wt. % of this DMAPA product, based on the total weight of the fully formulated lubricant composition, and the TBN was measured by ASTM D-2896 and ASTM D-4739. The composition was also evaluated using a Ball Rust Test to measure the corrosion, and the elongation ratio and tensile strength of seals exposed to the fully formulated lubricating oil was also evaluated.

Example 7

Butylimidazole was mixed with a fully formulated lubricant to provide 0.16 wt. % of the butylimidazole in the fully formulated lubricant composition, based on the total weight of the fully formulated lubricant composition, and the TBN was measured by ASTM D-2896 and ASTM D-4739. Butylimidazole has the following structure.

Example 8

The DMAPA compound of the Formula (III), can be prepared by reaction of polymaleic anhydride with a N,N-dimethyl-1,3-propanediamine. 35 g of poly(maleic anhydride-alt-1-octadecene) with an average Mn of 30,000-50,000 obtained from Sigma Aldrich having the formula

and 22 g of 150N oil were added to a reaction kettle fitted with a mechanical stirrer, nitrogen inlet, temperature probe, and reflux condenser. 17 g of N,N-dimethyl-1,3-propanediamine was added and the temperature was raised to 130° C. for 1 hour and 35 minutes. Then the composition was stirred at that temperature for 1 hour and 40 minutes. The temperature was then raised to 160° C. and then the mixture was distilled for 30 minutes. Next, the mixture was stripped under full vacuum for 1 hour before breaking vacuum and cooling.

This DMAPA compound reaction product was then mixed with a fully formulated lubricant to provide a lubricant composition containing 0.9 wt. % of this DMAPA compound, based on the total weight of the lubricant composition, and the TBN was measured by ASTM D-2896 and ASTM D-4739. The composition was also evaluated using a Ball Rust Test to measure the corrosion, and the elongation ratio and tensile strength of seals exposed to the fully formulated lubricating oil was also evaluated.

Example 9

The DMAPA compound of Formula (III), can be prepared by reaction of polymaleic anhydride with a N,N-dimethyl-1,3-propanediamine using the process as described in Example 9.

the prepared DMAPA compound of the Formula (III) was then mixed with a fully formulated lubricant to provide a lubricant composition containing 1.1 wt. % of the prepared DMAPA compound, based on the total weight of the fully formulated lubricant and the TBN was measured by ASTM D-2896 and ASTM D-4739. The composition was also evaluated using a Ball Rust Test to measure the corrosion, and the elongation ratio and tensile strength of seals exposed to the fully formulated lubricating oil was also evaluated.

The Ball Rust Test

The Ball Rust Test is a method of evaluating anti-corrosion properties of various oil formulations. In the Ball Rust Test, a ball bearing is immersed in an oil. Air saturated with acidic contaminants is bubbled through the oil for 18 hours at 40° C. After this 18-hour reaction period, the ball is removed from the test oil and the amount of corrosion on the ball is quantified using a light reflectance technique. The amount of reflected light is reported as an average gray value (AGV). The AGV for a fresh un-corroded ball is approximately 140. A totally corroded ball has an AGV result of less than 20. An oil with good anti-corrosion properties has an AGV greater than 50. This test method is described by EP 1 548 090 B1.

Seal Elongation and Tensile Strength

AK6 rubber was cut into bone shapes with ASTM D1822-61 Type L die cast and placed in 30 ml scintillation vial. About 20 g of blend oil was poured into the scintillation vial and the vial was tightly covered with aluminum foil. The vial was then placed in an oven maintained at 150° C. for 168 hours. The sample was removed from oven, cooled enough to handle and oil was decanted. Excess oil from the rubber bone was blotted with tissues. Seal elongation and tensile strength (TS %) were then measured using a Bluehill INSTRON Model #2519-104 and the elongation ratio (ER %) was then calculated.

Samples were tested to show that the TBN boosters of the present invention can provide lubricating oils that have TBN values as measured by ASTM D-2896 and ASTM D-4739 similar to or greater than achievable using larger amounts calcium sulfonate, while maintaining corrosion inhibition properties and, in some cases, reducing or minimizing damage to seals as measured by seal elongation and tensile strength. The data is shown in Tables 3 and 4 below.

TABLE 3 TBN as measured by TBN as measured by Example ASTM D-2896 ASTM D-4739 A 6.71 5.1 B 6.12 4.4 D 6.92 4.4 1 6.85 5.3 2 6.69 5.1 3 7.04 5.5 4 6.92 5.1 5 7.06 5.3 6 6.84 5.3 7 6.85 4.9 8 7.22 4.8 9 7.33 5.0

As shown in Table 3 above, the inventive compounds are capable of providing a fully formulated lubricating oil having a TBN as measured by ASTM D-2896 and ASTM D-4739 similar to or greater than the TBN of a similar lubricating oil containing calcium sulfonate at 1.3 wt. % and no TBN booster. Also, as seen in Table 4 the lubricating oils of the present invention showed improved inhibition to corrosion.

As shown in Table 4, TBN boosters provided with polymer backbone as in Examples 9-10 provided improved seal protection relative a similar TBN booster having the same active group but no polymer backbone chain. Thus, this shows that certain embodiments of the present invention can also be selected for their improved compatibility with seals, if necessary or desirable.

In conclusion, the object of the invention was achieved, because the TBN boosters provided lubricating oil compositions having a TBN as measured by ASTM D-4739 similar to or greater than the same TBN achieved using the calcium sulfonate detergent, while also maintaining good corrosion inhibition.

Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. As used throughout the specification and claims, “a” and/or “an” may refer to one or more than one. Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, percent, ratio, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about,” whether or not the term “about” is present. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and claims are approximations that may vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims.

The foregoing embodiments are susceptible to considerable variation in practice. Accordingly, the embodiments are not intended to be limited to the specific exemplifications set forth hereinabove. Rather, the foregoing embodiments are within the scope of the appended claims, including the equivalents thereof available as a matter of law. The patentees do not intend to dedicate any disclosed embodiments to the public, and to the extent any disclosed modifications or alterations may not literally fall within the scope of the claims, they are considered to be part hereof under the doctrine of equivalents. All patents and publications cited herein are fully incorporated by reference herein in their entirety. It is to be understood that each component, compound, substituent, or parameter disclosed herein is to be interpreted as being disclosed for use alone or in combination with one or more of each and every other component, compound, substituent, or parameter disclosed herein. It is also to be understood that each amount/value or range of amounts/values for each component, compound, substituent, or parameter disclosed herein is to be interpreted as also being disclosed in combination with each amount/value or range of amounts/values disclosed for any other component(s), compounds(s), substituent(s), or parameter(s) disclosed herein and that any combination of amounts/values or ranges of amounts/values for two or more component(s), compounds(s), substituent(s), or parameters disclosed herein are thus also disclosed in combination with each other. It is further understood that each lower limit of each range disclosed herein is to be interpreted as disclosed in combination with each upper limit of each range disclosed herein for the same component, compounds, substituent, or parameter. Furthermore, specific amounts/values of a component, compound, substituent, or parameter disclosed in the description or an example is to be interpreted as a disclosure of either a lower or an upper limit of a range and thus can be combined with any other lower or upper limit of a range or specific amount/value for the same component, compound, substituent, or parameter disclosed elsewhere in the application to form a range for that component, compound, substituent, or parameter. 

1. A lubricating oil composition comprising: a) greater than 50% by weight of a base oil, based on the total weight of the lubricating oil composition; and b) an additive selected from the group consisting of: i) a reaction product of a dicyclohexyl carbodiimide with a primary or a secondary amine; and ii) at least one compound of the Formula (I):

wherein R′, R″, and R′″ are independently selected from the group consisting of hydrogen and hydrocarbyl groups containing 1-50 carbon atoms.
 2. The lubricating oil composition as claimed in claim 1, wherein the additive is the reaction product of the dicyclohexyl carbodiimide with the primary or secondary amine.
 3. The lubricating oil composition as claimed in claim 2, wherein the reaction product is the reaction product of the dicyclohexyl carbodiimide with the primary amine.
 4. The lubricating oil composition as claimed in claim 2, wherein the reaction product is the reaction product of the dicyclohexyl carbodiimide with the secondary amine.
 5. The lubricating oil composition as claimed in claim 1, wherein the additive is one compound of the Formula (I).
 6. The lubricating oil composition as claimed in claim 5, wherein R′ is an alkyl group having from about 4 to about 15 carbon atoms.
 7. The lubricating oil composition as claimed in claim 5, where R″ is a hydrocarbyl group having from about 6 to about 12 carbon atoms and R′″ is a hydrocarbyl group having from about 6 to about 12 carbon atoms.
 8. The lubricating oil composition as claimed in claim 5, wherein the compound of Formula (I) is selected from the group consisting of N-dodecyl-N′N″-dicyclohexylguanidine, N-2-ethylhexyl-N′, N″-dicyclohexylguanidine, N-benzyl-N′,N″-dicyclohexylguanidine, N-cyclohexyl-N′-dicyclohexyl-N″-cyclohexylguanidine, N,N-dihexyl-N′,N″-dicyclohexylguanidine and N-oleyl-N′,N″-dicyclohexylguanidine.
 9. The lubricating oil composition as claimed in claim 1, wherein the lubricating oil composition further comprises an overbased calcium sulfonate detergent.
 10. The lubricating oil composition as claimed in claim 9, wherein the lubricating oil composition comprises no more than 2 wt. % of an overbased calcium detergent based on the total weight of the lubricating oil composition and the lubricating oil composition has a total sulfated ash content of about 2 wt. % or less, or about 1.5 wt. % or less, based on the total weight of the lubricating oil composition.
 11. The lubricating oil composition as claimed in claim 1, wherein the lubricating oil composition comprises a sufficient amount of the reaction product or the compound of the Formula (I) to boost the TBN of the lubricating composition by from about 0.2 to about 2, or from about 0.4 to about 1.5, or from about 0.5 to about 1.2, wherein the TBN boost is determined using the TBN measurement method of ASTM D-4739.
 12. The lubricating oil composition as claimed in claim 1, wherein the lubricating oil composition comprises from about 0.01 to about 2 wt. % of the reaction product or the compound of the Formula (I), or from about 0.1 to about 1.8 wt. % or from about 0.25 to about 1.5 wt. %, based on the total weight of the lubricating oil composition.
 13. The lubricating oil composition as claimed in claim 1, wherein lubricating oil composition is an engine oil composition and the base oil is selected from the group consisting of Group II, Group III, Group IV, Group V base oils having at least 90% saturates, and any mixture thereof.
 14. The lubricating oil composition as claimed in claim 1, wherein the lubricating oil composition further comprises at least one additive selected from the group consisting of antioxidants, antifoam agents, molybdenum-containing compounds, titanium-containing compounds, phosphorus-containing compounds, viscosity index improvers, pour point depressants, and diluent oils.
 15. A lubricating oil composition comprising: a) greater than 50% by weight of a base oil, based on the total weight of the lubricating oil composition; and b) an additive selected from the group consisting of: i) a reaction product of N,N-dimethyl-1,3-propanediamine with at least one compound of the following Formulas (II)-(III):

 wherein R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms, R₂ is selected from hydrogen, or a hydrocarbyl group of 1-50 carbon atoms; and in the compounds of the Formula (III) n is selected to provide a total number average molecular weight of from about 10,000 to about 70,000, or from about 20,000 to about 60,000, or from about 30,000 to 50,000; ii) at least one compound of the following Formulas (IV)-(V):

 wherein R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms and R₂ is selected from hydrogen, or a hydrocarbyl group of 1-50 carbon atoms, R₇ is an amino group and in the compounds of the Formula (IV) n is selected such that the compounds have a total number average molecular weight Mw of 10,000 to 70,000, or from about 20,000 to about 60,000, or from about 30,000 to 50,000; and iii) a compound of the Formula (VI)

wherein R5 is a hydrocarbyl group having 1-20 carbon atoms.
 16. A method for boosting TBN as measured by both ASTM D-2896 and ASTM D-4739 without increasing the ash content of a lubricating composition, comprising the step of adding to the lubricating oil composition an additive selected from the group consisting of: i) a reaction product of a dicyclohexyl carbodiimide with a primary or a secondary amine; and ii) at least one compound of the Formula (I):

wherein R′, R″, and R′″ are independently selected from the group consisting of hydrogen and hydrocarbyl groups containing 1-50 carbon atoms.
 17. The method as claimed in claim 16, wherein a boost in the TBN as measured by ASTM D-4739 is from about 0.2 to about 2, or from about 0.4 to about 1.5, or from about 0.5 to about 1.2.
 18. A method for improving the performance as measured by a Ball Rust Test in an engine, comprising the step of adding to the lubricating oil composition an additive selected from the group consisting of: i) a reaction product of a dicyclohexyl carbodiimide with a primary or a secondary amine; and ii) at least one compound of the Formula (I):

wherein R′, R″, and R′″ are independently selected from the group consisting of hydrogen and hydrocarbyl groups containing 1-50 carbon atoms.
 19. The method as claimed in claim 18, wherein the improvement in the performance in the Ball Rust Test is determined relative to a same lubricating composition in the absence of the TBN booster.
 20. A method for boosting TBN as measured by both ASTM D-2896 and ASTM D-4739 without increasing the ash content of a lubricating composition, comprising the step of adding to the lubricating oil composition an additive selected from the group consisting of: i) a reaction product of N,N-dimethyl-1,3-propanediamine with at least one compound of the following Formulas (II)-(III):

wherein R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms, R₂ is selected from hydrogen, or a hydrocarbyl group of 1-50 carbon atoms; and in the compounds of the Formula (III) n is selected to provide a total number average molecular weight of 10,000 to 70,000, or from about 20,000 to about 60,000, or from about 30,000 to 50,000; ii) at least one compound of the following Formulas (IV)-(V):

wherein R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms and R₂ is selected from hydrogen, or a hydrocarbyl group of 1-50 carbon atoms, R₇ is an amino group and in the compounds of the Formula (IV) n is selected such that the compounds have a total number average molecular weight Mw of 10,000 to 70,000, or from about 20,000 to about 60,000, or from about 30,000 to 50,000; and iii) a compound of the Formula (VI)

wherein R5 is a hydrocarbyl group having 1-20 carbon atoms.
 21. The method as claimed in claim 20, wherein a boost in the TBN as measured by ASTM D-4739 is from about 0.2 to about 2, or from about 0.4 to about 1.5, or from about 0.5 to about 1.2.
 22. A method for boosting the performance as measured by a Ball Rust Test in an engine, comprising the step of adding to the lubricating oil composition an additive selected from the group consisting of: i) a reaction product of N,N-dimethyl-1,3-propanediamine with at least one compound of the following Formulas (II)-(III):

wherein R1 is selected from a hydrocarbyl group of 1-50 carbon atoms, R2 is selected from hydrogen, or a hydrocarbyl group of 1-50 carbon atoms; and in the compounds of the Formula (III) n is selected to provide a total number average molecular weight of 10,000 to 70,000, or from about 20,000 to about 60,000, or from about 30,000 to 50,000; ii) at least one compound of the following Formulas (IV)-(V):

wherein R₁ is selected from a hydrocarbyl group of 1-50 carbon atoms and R₂ is selected from hydrogen, or a hydrocarbyl group of 1-50 carbon atoms, R₇ is an amino group and in the compounds of the Formula (IV) n is selected such that the compounds have a total number average molecular weight Mw of 10,000 to 70,000, or from about 20,000 to about 60,000, or from about 30,000 to 50,000; and iii) a compound of the Formula (VI)

wherein R₅ is a hydrocarbyl group having 1-20 carbon atoms, wherein the performance in the Ball Rust Test is determined relative to a same lubricating composition in the absence of the TBN booster. 